"protect the idea" is correct and usable in written English.
You can use it when you want to emphasize the importance of an idea or concept. For example: "We must protect the idea of individual liberty at all costs."
I didn't protect the idea of the book; I protected the final work product — postexecution.
"I think after Sept. 11, people have been very much wanting to protect the idea of their own little space.
We try to protect the idea of free will, while the possible space for its operation shrinks.
Some experts wonder if Libya might become the first experiment in the use of the "responsibility to protect" — the idea that a United Nations force would be deployed to prevent civilian deaths in the event of widespread violence.
It is even enshrined in a United Nations-approved covenant as the "responsibility to protect" — the idea being that a state that engages in criminal behavior toward its own people has forfeited not just its moral but also its legal right to sovereignty.
The Copyright Office has stated that copyright law does not protect the idea of a game by itself.
But they argue as well that the laws that protect them also protect the ideas of upstart innovators.
And even if a law were warranted to protect the ideas and bank accounts of the designers, how would it work, anyway?
'I still want to protect my personal life, but I don't want to seem like I'm protecting the idea, so that does sort of feel like I owe something to people.'" 6.
"It's not so much to do with the physical fabric, but protecting the spirit of the building, protecting the idea, making sure you are discharging your responsibility to the past but also just as importantly you are setting up the conditions where the theatre can continue its role into the future for generations of theatre audiences".
So in some instances, when you think "Oh, we can't do this", you're actually protecting the idea that someone was buried there when there's [often] nothing left.
